linux.git/tools/testing/selftests/powerpc, branch v5.1

selftests/powerpc: Remove duplicate header

2019-02-26T01:32:06+00:00

Remove duplicate headers which are included twice.

Signed-off-by: Sabyasachi Gupta 
Signed-off-by: Souptick Joarder 
[mpe: Split out of larger patch]
Signed-off-by: Michael Ellerman

powerpc/selftest: fix type of mftb() in null_syscall

2019-02-21T13:10:15+00:00

All callers of mftb() expect 'unsigned long', and the function itself
only returns lower part of the TB so it really is 'unsigned long'
not 'unsigned long long'

Signed-off-by: Christophe Leroy 
Signed-off-by: Michael Ellerman

selftests/powerpc: New TM signal self test

2019-01-15T00:17:09+00:00

A new self test that forces MSR[TS] to be set without calling any TM
instruction. This test also tries to cause a page fault at a signal
handler, exactly between MSR[TS] set and tm_recheckpoint(), forcing
thread->texasr to be rewritten with TEXASR[FS] = 0, which will cause a BUG
when tm_recheckpoint() is called.

This test is not deterministic, since it is hard to guarantee that the page
access will cause a page fault. In order to force more page faults at
signal context, the signal handler and the ucontext are being mapped into a
MADV_DONTNEED memory chunks.

Tests have shown that the bug could be exposed with few interactions in a
buggy kernel. This test is configured to loop 5000x, having a good chance
to hit the kernel issue in just one run.  This self test takes less than
two seconds to run.

This test uses set/getcontext because the kernel will recheckpoint
zeroed structures, causing the test to segfault, which is undesired because
the test needs to rerun, so, there is a signal handler for SIGSEGV which
will restart the test.

v2: Uses the MADV_DONTNEED memory advice
v3: Fix memcpy and 32-bits compilation
v4: Does not define unused macros

Signed-off-by: Breno Leitao 
Signed-off-by: Michael Ellerman

selftests/powerpc: Add checks for transactional sigreturn

2018-12-21T03:46:50+00:00

This is a new test case that creates a signal and starts a suspended
transaction inside the signal handler.

It returns from the signal handler with the CPU at suspended state, but
without setting user context MSR Transaction State (TS) field.

The kernel signal handler code should be able to handle this discrepancy
instead of crashing.

This code could be compiled and used to test 32 and 64-bits signal
handlers.

Signed-off-by: Breno Leitao 
Signed-off-by: Gustavo Romero 
Signed-off-by: Michael Ellerman

selftests/powerpc: Skip test instead of failing

2018-11-25T06:11:22+00:00

Current core-pkey selftest fails if the test runs without privileges to
write into the core pattern file (/proc/sys/kernel/core_pattern). This
causes the test to fail and give the impression that the subsystem being
tested is broken, when, in fact, the test is being executed without the
proper privileges. This is the current error:

	test: core_pkey
	tags: git_version:v4.19-3-g9e3363be9bce-dirty
	Error writing to core_pattern file: Permission denied
	failure: core_pkey

This patch simply skips this test if it runs without the proper privileges,
avoiding this undesired failure.

CC: Tyrel Datwyler 
CC: Thiago Jung Bauermann 
Signed-off-by: Breno Leitao 
Reviewed-by: Thiago Jung Bauermann 
Signed-off-by: Michael Ellerman

selftests/powerpc: Create a new SKIP_IF macro

2018-11-25T06:11:22+00:00

This patch creates a new macro that skips a test and prints a message to
stderr. This is useful to give an idea why the tests is being skipped,
other than just skipping the test blindly.

Signed-off-by: Breno Leitao 
Reviewed-by: Thiago Jung Bauermann 
Signed-off-by: Michael Ellerman

selftests/powerpc: Allocate base registers

2018-11-25T06:11:21+00:00

Some ptrace selftests are passing input operands using a constraint that
can allocate any register for the operand, and using these registers on
load/store operations.

If the register allocated by the compiler happens to be zero (r0), it might
cause an invalid memory address access, since load and store operations
consider the content of 0x0 address if the base register is r0, instead of
the content of the r0 register. For example:

	r1 := 0xdeadbeef
	r0 := 0xdeadbeef

	ld r2, 0(1) /* will load into r2 the content of r1 address */
	ld r2, 0(0) /* will load into r2 the content of 0x0 */

In order to avoid this possible problem, the inline assembly constraint
should be aware that these registers will be used as a base register, thus,
r0 should not be allocated.

Other than that, this patch removes inline assembly operands that are not
used by the tests.

Signed-off-by: Breno Leitao 
Reviewed-by: Segher Boessenkool 
Signed-off-by: Michael Ellerman

selftests/powerpc: Adjust wild_bctr to build with old binutils

2018-11-15T12:05:17+00:00

Currently the selftest wild_bctr can fail to build when an old gcc is
used, notably on gcc using a binutils version <= 2.27, because the
assembler does not support the integer suffix UL.

This patch adjusts the wild_bctr test so the REG_POISON value is still
treated as an unsigned long for the shifts on compilation but the UL
suffix is absent on the stringification, so the inline asm code
generated has no UL suffixes.

Signed-off-by: Gustavo Romero 
[mpe: Wrap long line]
Signed-off-by: Michael Ellerman

selftests/powerpc: Fix wild_bctr test to work on ppc64

2018-11-12T03:47:54+00:00

The selftest I recently added to test branching to an out-of-bounds
NIP doesn't work on 64-bit big endian. It does fail but not in the
right way. That is it SEGVs trying to load from the opd at BAD_NIP,
but it never gets as far as branching to BAD_NIP.

To fix it we need to create an opd which is reachable but which holds
the bad address.

Fixes: b7683fc66eba ("selftests/powerpc: Add a test of wild bctr")
Signed-off-by: Michael Ellerman

selftests/powerpc: Fix compilation issue due to asm label

2018-10-31T23:06:03+00:00

We are using 'dscr_insn' as a label in inline asm to identify if a
SIGILL was generated by the mtspr instruction at that point. However,
with inline assembly, the compiler is still free to duplicate the asm
statement for optimization purposes, which results in the label being
defined twice with the error:
	/tmp/ccerQCql.s:874: Error: symbol `dscr_insn' is already defined

With different compiler versions, we may also see:
	/tmp/ccJzLDlN.o:(.toc+0x0): undefined reference to `dscr_insn'

Remove the use of the label in the inline assembly. Instead, just look
for the offending instruction in the signal handler.

Fixes: d2bf793237b3 ("selftests/powerpc: Add test to verify rfi flush across a system call")
Reported-by: Breno Leitao 
Signed-off-by: Naveen N. Rao 
Tested-by: Breno Leitao 
Signed-off-by: Michael Ellerman